Apparatus for roasting and cooling ores.



No. 700,135. Paton ted May l3, I902.

v w. c. DAVIS.

APPARATUS FOR ROASTING AND COOLING-BEES.

(Application filed Jan. 6, 190B.) (No Model.) l0 Sheets-Sheet 2.

W] T NESSES In [N VEN T OR.

AIZTORNEY.

THE miams pzrzRs coy, PHOTO-UTHO" wunmu'rdu. u. c.

No. 700,!35. I Patented May l3, I902.

W. 6. DAVIS.

APPARATUS FOR ROASTING AND COOLING DBES. I

(Applichtion filed Jan. 6, 1902.) (No Ilodal.) I0 Sheets$haet 3.

WITNESSES: INVENTOR.

g, zhj/A 4727M;

L By I ATTORNEY.

- Patented May l3, I902.

A w c. DAVIS. APPARATUS FOR RUASTING AND COOLING OBES.

(Application filed Jan. 6, 1902.)

lo Sheets$haet 4.

(N0 ModeL;

llllll ljilllllh WITNESSES 22 6. 9

I INVENTOR. Zfi /AQ/y 407M 8) 1 I ATTORNEY.

m: uunms PETERS co.. PnoTouTHu WASHINGYON u c IUShaets Sheet 5.

(Ito Model.)

11V VENT OR. 4% l/w y 6 WITNESSES ATTORNEY.

No. 7o0,|35. I Patented May-l3, I902;

' w. c. DAVIS.

APPARATUS FUR RUASTING AND COOLING ORES.

N o. 700,|35. .Patented May I3, [902.

w. c. DAVIS. APPARATUS FOR ROAST'ING AND COOLING (IRES.

(Application filed Jan; 6, 1902) (No Model.) 10 Sheets-Sheet 7.

WITNESSES: INVENTOR.

ATTORNEY.

TH: Noams PETERS co PNOTO-LITHCL. WASHINGTON. a c.

N0. 700,!35. Pafented May I3, 1902. w. c. DAVIS. APPARATUS r00 ROASTINGAND couuus ones.

(Application filed 3m. 6, 1902.) (No Model.) In $heets8heet a'.

IV I'LVESSES: 1N VENT 0R.

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ATTORNEY.

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No. 7oo',|'3 5.' Patented May 13, I902.

- y w. c. DAVIS.-

APPABATUS FOR ROASTING AND COOLING OBES.

(Application filed Jan. 6, 1902.)

(No Model.)

H] Sheets-8heet 9.

I JNVENTIOR. J/I /A 27m; B2

ATTORNEY.

No. 700,|35. Patented May I3, 1902. w. c. DAVIS.

APPARATUS FOR RDASTI NG AND COOLING ORES.

(Application filed Jan. 6, 1902.)

lo Shets-Shaet in.

(No Model.)

WITNESSES: I JNVENTOR:

UNITED STATES P TENT. OFFICE.

YVILLIAM C. DAVIS, OF DENVER, COLORADO.

APPARATUS FOR ROASTING AND COOLING ORES.

SPECIFICATION forming part of LettersfIEaten't No. 700,135, dated May13, 1902.

. Application filed January 1602. serial No. 83,691 (No model.)

To all whognitntay conccrm' Be it known that-I, WILLIAM C. DAVIS, a

' citizen of the U nited States of America, residing at Denver, in thecounty of Arapahoe and State of Colorado, have invented certain new anduseful Improvements in Apparatus for Roasting and Cooling Ores; and'I dodeclare I the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art 'to whichit appertains to make and-use the same, reference being had to theaccompanying drawings, and to the characters of reference markedthereon, which form a part of this specification.

My invention relates to improvements in apparatus for roasting andcooling ores preparatory to treatment for the purpose of saving theirmetallic values. As is well known to those skilled inthe art,theroasting operation is for the purpose of removing certain elements,as sulfur, arsenic, &c., which render the ores in their natural staterefractory,

whereby it becomes impracticable to separate the values from the gangue.After the roasting operation is complete the ore, which is in a highlyheated condition, must be cooled before it can be treated. My presentobject is to provide a thoroughly practical apparatus for successivelyperforming the ore roasting andcooling functions.

In order that the invention may be perfectly understood, I will firstpoint out in a very general way some of the main features of theinvention preparatory to the detailed description, which will befollowed by the claims.

The apparatus comprises an inclosed roasting-hearth and an exposedcooling-hearth located above the roasting-chamber. Within theroasting-chamber, which is in communication with the necessary source ofheat, is a rabble-carriage propelled by wheels located in pockets formedadjacent and along the outer edges of the roasting-hearth, said wheelsbeing operated by suitable shafts and gears located outside of theroasting chamber. The rabble carriage consists of hollow side barshaving cogged racks on their lower edges arranged to mesh with the cogsof the propelling-wheels. These side bars of the carriage comprisewater-receptacles and are connected by hollow transverse bars, throughwhich the water circulates to prevent injury to the apparatus from thehigh degree of heat maintained in the roasting-chamber. On one of thehollow transverse bars is loosely 1nount ed a sleeve, to which aresecured the rabble blades or plows. Provision is made for antomaticallyreversing the rabble-carriage-opcrating mechanism when the carriage hasreached either end of the roasting-chamber, whereby the carriage beginsits reverse movement. Provision is also made for automaticallyreplenishing the carriage water-supply when the carriage has reached itslimit of movement in one direction; Means are further provided forgiving the rabble-sleeve a quarter-turn at each extremity of theroasting-chamber, whereby the rabble-blades are held in an inoperativeposition during the return or forward movement and in an operativeposition during the rearward movement, and finally means are providedfor receiving the roasted ore as it is dischaged at the rear extremityof the roasting-chamber and carrying it automatically to thecooling-hearth above, Where it is acted on by a. rabble constructionsimilar to that in the roasting-cham ber, except that the water-coolingfeature is absent, for the reason that it is not needed, thecooling-hearth being located in the open air. The invention will now bedescribed in detail, reference being made to the accompanying drawings,in which is illustrated an embodiment thereof.

In the drawings, Figure 1 is a side elevation of the forward portion ofmy roasting and cooling apparatus, the smoke-flue leading from theroasting-chamber to the stack being shown in section. Fig. 2 is a viewof the central portion of the apparatus, showing a fire-box in section.Fig. 3 is a similar view of the rear portion of the apparatus, the fluethrough which the chute for the discharge of the roasted ore passesbeing shown in section. Fig. 4 is a fragmentary horizontal section takenthrough the roasting-chamber above the hearth, which is shown in plan.In this view the parts are shown on a larger scale than in Figs. '1, 2,and 3. Fig. 5 is a section taken through the roasting-chamber, cuttingone of the fire-boxes. Fig. 6 is a similar section taken on the line 25, Fig. 4. Fig. 7 is an end view of the apparatus, illustrating the cooling-hearth, and its rabble mechanism. Fig. 8 is a cross-section takenthrough the roasting-chamber,showing the rabble-carriage and itsoperating mechanism in end view. Fig. 9 is a detail view showing aspecific bearing adjustment enlarged. Fig. 10 is an enlarged elevation,partly in section, of the forward extremity of the apparatus,illustrating the means for supplying the rabble-carriage with water andthe construction for transmitting motion from the lower to the upperoperating-shafts. Fig. 11 is an enlarged sectional view of the rearextremity of the apparatus, illustrating the manner of elevating theroasted ore from the discharge extremity of the roasting-chamber to thecooling-hearth above. Figs. 12 and 13 are detail views illustrating themechanism for turning the rabble-sleeve on the transverse bar of therabblecarriage. In these views the trip is shownin two positionscorresponding with the direction of travel of the rabble-carriage. Figs.14 and 15 illustrate the rabble-plows viewed in two positions. Fig. 16is a fragmentary top view of the rear extremity of the apparatus,showing the elevator-bucket in the position designated 13 in Fig. 11.

The same reference characters indicate the same parts in all the views.

Figs. 1, 2, and 3 illustrate the complete apparatus, which is shown onthree sheets for lack of space on a single sheet.

Let the numeral 5 designate the walls of the roasting-chamber, whichwalls are supported on opposite sides by buckstays 6. The top of thischamber is arched in the usual manner, and it may be of any desiredlength. Only one fire-box 7 for supplying the necessary heat for theproper calcining or desulfurization of the ore is shown. It must beunderstood, however, that in an apparatus of ordinary length a number ofthese fire-boxes will preferably be employed. They are arranged alongthe sides of the apparatus and communicate with the roasting oroxidizing chamber 8 by way of a lateral fine 9, the heat and products ofcombustion passing over a bridge-wall 10. (See Fig. 5.) Theroastinghearth 12 forms the bottom of the combustion or roastingchamber, and the ore to be treated is fed to the roasting-hearth from ahopper 13 (see Fig. 4) through the instrumentality of-a feed-screw14,located in a narrow chamber 15 below the bed of the hearth andcommunicating with the roasting-chamber. The ore is delivered to thehearth at the forward or left-hand extremity of the roasting-chamber,referring to Fig. 1. As the ore is forced into the recess or transversefeedchamber 15 and accumulates therein it is forced upwardly by theincoming ore above the bed of the hearth and is distributed over thelatter by the plows or blades mounted on the rabble-carriage, which willnow be described in detail. This carriage consists of two hollow bars16, occupying positions parallel with each other and on opposite sidesof the roasting-hearth 12. The ends of these bars are closed, formingthem into water troughs or receptacles, which are open at the top. Theseside bars are connected by hollow transverse bars 17, whose ends areopen and in communication with the hollow side bars, whereby the waterdischarged into the side bars fills the hollow of the transverseconnecting-bars and is allowed to circulate freely therethrough forcooling purposes. The water supplied to the rabble-carriage willnaturally escape by evaporation within the roasting-hearth. Henceprovision is made for replenishingthe water at predeterminedintervals-namely, every time the carriage is moved back and forth thelength of the roasting-chamber or madeacomplete trip,as willbefullyexplained hereinafter. As shown in the drawings, upon the centralhollow bar 17 is mounted a sleeve 18, arranged to turn on the bar. Tothis sleeve are secured on opposite sides the rabble plows or blades 19,which occupy positions diagonally or inclined to the direction of travelof the rabble-carriage. These blades or plows are so arranged that whenmaking one trip in the rearward direction or toward the dischargeextremity of the apparatus the ore is moved outwardly in both directionsfrom the center of the hearth simultaneously with the rearward movementon the hearth,while when making the next trip rearwardly the ore ismoved inwardly from the outer edges toward the center of the hearth. Bythis arrangement the ore while moving rearwardly toward the dischargeend of the apparatus -is repeatedly turned over in opposite directionsduring the successive trips of the rabble-carriage in theroasting-chamber or over the roasting-hearth, whereby it is completelyand thoroughly stir-red or agitated, bringing every particle intointimate contact or relation with the heat from the fire-box and theoxygen of the air, to the end that the roasting or desulfurizingfunction may be properly performed. To this end the rabble-plows of theright and left halves of the rabble-sleeve, referring to Fig. 4, areoppositely inclined. It will be understood by referring to Fig. 15 thatthere are two sets of rabble blades or plows diametrically located onthe rabblesleeve, the blades of one set being parallel with those of theother set. Provision is made for turning this sleeve whereby the twosets of rabble-plows act alternately on the ore during the successiverearward movements of the rabble-carriage. Hence the blades whenprojecting upwardly and out of contact with the ore, are'inclined in onedirection and occupy positions parallel with the downwardlyprojectingblades, will be oppositely inclined when the sleeve is given a half-turnon its axle or hollow bar 17, whereby the blades which were previouslyinoperative, are brought in operative relation with the ore. Therabblesleeve 18 is composed of a series of interlocking sections 18.(Clearly distinguishable in Figs. 14 and, 15, but not shown in the otherfigures on account of the reduced scale necessarily employed.)

A pair of diametrically-located rabble plows A or blades is attached toeach sleeve-section tact therewith. Hence during the forward movementthe rabble-plows are idle.

In order that a partial rotation of the rabble-sleeve may beautomatically accomplished at proper intervals, a toothed wheel is madefast to the rabble-sleeve at each extremity. (See Figs. 12 to 14,inclusive.) This wheel 20 is allowed to rotate freely with its sleeve inthe direction indicated by the arrowin Figs. 12 and 13, while it islocked against movement in the opposite direction by a dog 21, pivotallymounted, as shown at 22, on one of the side bars 16 of therabble-carriage. This dog is weighted at one extremity, as shown at 23,

whereby it normally assumes the position shown by full lines in Figs. 12and 13. Depending from .the roof of the roasting-chama her and locatedat each extremity thereof is a tripping device 24, pivotally mounted onthe lower extremity of a bolt 25, which passes throughthe roof of theroasting-chamber and is secured by nuts on the outside. This trip 24isprovided with a projection 24, which looks the trip against movementin the direction indicated by the arrow when the trip is in theverticalv position, as shown at Fig. 13, but allows it to move freely ini the opposite direction. Hence, assuming that the rabble carriage istraveling forward or in the direction indicated by the feathered arrowin Fig.

- 12 and the rabble-plows are inthe position indicated by dotted linesin the same figure, the toothed wheel 20 will pass under the trip, thelatter yieldingreadily for the purpose. As soon, however, as therabble-carriage begins the returnor rearward movement in the directionindicated by the feathered arrow in Fig. 13 the toothed wheel engagesthe trip from the opposite side, and the resistance of the latter causesthe wheel. and therabblesleeve to turn one-fourth of a revolution,throwing the rabble-plows in the position indicated by dotted lines inFig. 13. As the toothed wheel turns the dog 21 moves to the positionshown by dotted lines in Fig. 12 until a tooth of the wheel has passedthe holding extremity of the dog, when the latter will return to itsnormal position, locking the wheel and rabble-sleeve against movement inthe opposite direction. As the toothed wheel 20 and the rabble-sleevealways turn in the same direction, the set of rabble-plows which isuppermost or inoperative during one rearward trip of the rabble-carriagewill be lowermost or in engagement with the ore during the next rearwardtrip of the carriage; hence the action of the rabble-plows whereby theore is thrown outwardly during one rearward movement and inwardly duringthe next rearward movement of the carriage.

The rabble-carriage is propelled by carrierwheels 26, located in pockets27 formed on opposite sides of the roasting-hearth. The peripheries ofthese wheels are cogged, as shown at 26, to engage a cogged rack 16,with which the bottom or lower edge of each side bar 16 is provided.Each wheel 26 is also provided with a plain or uncogged zone 26, whichis. engaged by a depending plain part 16 of each bar. The carriage issup ported on the plain zones of the wheels, whereby the cogs of theracks and wheels are prevented from meshing tightly or pinching at thebottoms of the teeth. Hence the cogged zones of the wheels perform thepropelling function and their plain portion the supporting function.Thesewheels 26 are also pro vided with interior flanges 26, which holdthe side bars in operative relation on the wheels. These carrier-wheels26 are made fast to short shafts 27, journaled in suitable bearings 28,located in openings 29," formed in the side walls of theroasting-chamber. To the outer extremities of shafts 27 are made fastbeveled gears 30, which mesh with similar gears 31, fast on-1ong shafts32, located on 1 the outside of the roasting-chamber and extending theentire length thereof on opposite sides. These shafts are connected atthe'forward end of the apparatus by a transverse shaft 33, provided atits extremities with beveled gears 34, meshing with similar gears 35,

and 39, connected with the same line-shaft.

ble-carriage is made to travel back and forth in the roasting-chamber.As shown in the drawings, the straight belt engagesthe. pulley 37, hasbeen just shifted to this position from the loose pulley 41, by abelt-shifter 42, while another belt-shifter 43, has thrown the belt 39from'the fast pulley 36 to theloose pulley40. Both belt-shiftersarefaston a rock-shaft 44, to which a crank-arm 45, provided with aweight 45 is also secured. This.

weight has atendency to, maintain the beltshifting mechanismin thedesired position of &

adjustment. This weighted crank-arm is connected by means of a link46'with one extremity of a crank-arm 47, whose opposite'extremity isfast on a shaft 48. One extremity of an arm 49 is also secured to therock-shaft 48,while its free extremity is arranged to be engaged by aside bar 16 of the rabble-carriage. These side bars 16 of the carriageprotrude from the roasting-chamber at both ends of the apparatus throughopenings formed in the end walls of the chamber. As the carriageapproaches its limit of forward movement the forward extremity of one ofthe side bars 16 engages the arm 49 and imparts a partial rotation tothe shaft 48, this movement being sufficient to perform thebelt-shifting function through the instrumentality of the partsdescribed. The motion of the shafts 32 is then reversed, as is also therotation of the propelling-wheels 26 within the roasting-chamber,whereby the rabble-carriage begins the reverse or rearward movement. Therock-shaft 48 is also provided with a rocking bar 50, fast on the shaftand projecting equally therefrom in opposite directions. The extremitiesof this bar are respectively connected with two rods or cables 51, whoseopposite extremities are connected with the extremities of a similarrocking bar 52, fast on a crank-shaft 53, located at the oppositeextremities of the apparatus, and to which is also secured a crankarm54, lying in the path of one of the side bars 16 of the rabble-carriage,as the latter approaches its rearward limit of movement. As theextremity of the side bar 16 engages the arm 54 the latter is movedsufficiently to impart a partial rotation to the rock-shaft 53, themovement of this shaft being sufficient to operate the belt-shiftingapparatus through the instrumentality of the connecting-rods 51, wherebythe straight belt 38 will be shifted to the loose pulley 41 and thecrossed belt 39 to the fast pulley 36, whereby the rotation of theshafts 32 will be again reversed and the rabble-carriage will begin theforward movement.

The propelling-wheels 26 within the roasting-chamber are located at suchintervals that one of them is always in engagement with each side bar 16of the carriage. In addition to these propelling-wheels a number ofplain or uncogged carrier-wheels 55 are employed. These wheels arelocated intermediate the propelling-wheels and are fast on shafts 56,journaled in bearings 28. The wheels 55 of course have no propellingfunction, but give additional support to the rabble-carriage.

Mounted at the front end of the roastingehamber is a transversewater-supply pipe 56, having two depending outlet branches 57, providedwith valves 58, which are normally closed. These branch pipes 57 are soarranged that when the valves are open and the rabble-carriage at itsforward limit of movement, the hollow bars 16 will be in position toreceive the water from the said outlet branches, whereby therabble-carriage receives a fresh supply of water every time it reachesits limit of forward movement.

For the purpose of automatically controlling the valve 58 its stem isprovidedwith a fast crank-arm 59. (Best shown in Fig. 10.) Thevalve-controlling devices are not shown in Fig. 7. The outer extremityof the crankarm 59 is connected by means of a link '60 with an arm 61 ofa triple-armed lever 61, fulcrumed at 62. The other two arms of thelever are designated 61 and 61, respectively. Normally the arm 61occupies a position in the path of one of the side bars 16 of therabble-carriage as the latter approaches its forward limit of movement.As the carriage continues its movement the forward extremity of eachside bar 16 engages a leverarm 61" and throws the lever 61 to theposition shown in Figs. 1 and 10, with the arm 61 resting on the top ofa hollow bar 16 and the arm 61 projecting thereinto. The normal positionof the arm 61 is just above the plane of the top of the bar. The arm 61is of sufficient width to cause it to rest on top of the side bar whenthe latter is in the position shown in Figs. 1 and 10. Normally this arm61 forms a door to close the opening in the end wall of theroasting-chamber, through which the side bar of the carriage protrudes.

The movement of the lever 61, just described, actuates the crank-arm 59sufficiently to open the valve 58 by virtue of the link conneetionbetween the arm and the lever, and water is discharged into thehollow'bar from the branch or discharge'pipe 57. The valveoperatingapparatus just described is doubled, there being one set of mechanismfor each bar 16, whereby there is a flow of water into both hollow sidebars 16 of the rabblecarriage simultaneously. It will be understood thatthe belt-shifting mechanism heretofore described is operatedsimultaneously with the opening of the valves 58, whereby the motion ofthe shafts 32 is reversed. Hence by the time the carriage is suppliedwith the necessary water it will be given its return or rearwardmovement.

The arm 61 of each valve-operating lever when the valve is open lies inthe path of the end wall of the hollow bar 16 as the carriage movesrearwardly. Hence the end of the bar 16 will engage this arm and returnthe lever to its normal position, closing the valve 58 and shutting offthe water, returning the lever-arm 61 to position to be again actuatedby the bar 16 when the carriage returns to the forward extremity of theroasting-chamher. The arm 61 of the lever is provided with a weight 61whose tendency is to maintain the valve ina closed position. The endwall of the roasting-chamber adjacent the valve-opening lever is open,as shown at 5, to allow the hollow bar 16 of the carriage to pass out ofthe roasting-chamber and also to allow the bar 61 to swing inwardlysimultaneously with the rearward movement of the carriage. A metal plateetis attached to this pelling-wheels 67.

end wall of the chamber and is provided with an opening, as shown at at,to register with the wall-opening. This opening in the end wall of thefurnace is closed by the part 61 when the hollow bar 16 moves into theroasting-chamber.

Above the arch or roof of the roasting-chamberis located acooling-hearth 63, which is supported by transverse I-beams 64, restingvon the upper extremities of the buckstays 6. Journaled in suitablebearings 65, mounted on the I-beams, are short shafts 66, to which aremade fast propelling-wheels 67, which are substantially of the sameconstruction as the wheels 26 of the roasting-chamber. Journaledin'bearings 6'7 are short shafts 68, to which are'made fastcarrier-wheels69, which are similar in every respect to the wheels 55 ofthe roasting-chamber. These propelling-wheels (57 are operated bylongitudinal shafts 70, geared to the shafts 66 by beveled gears 71 and72. Upon these propelling-and track wheels is mounted a rabblecarriagefor the. cooling-hearth consisting of sidebars 73, provided with coggedracks 74, arranged to mesh with the cogs of, the pro- These sidebars areconnected by transverse bars 75 in the same manner as therabble-carriage of the roastinghearth. In fact the carriage of thecoolinghearth is substantially of the same construction as that of theroasting-chamber, except coolihg-hearth carriage is movably mounted asleeve 76, carrying rabble blades or plows 78, connected and arrangedsubstantially the same as the corresponding parts of the roasting-hearthcarriage. 'The:rabble-sleeve is provided at each extremity witha'toothed wheel 79, which is engaged by adepending tripping device 80,mounted on abar 81, supported above the roasting-hearth by standards 82,mounted on the I-beams 641. The operation of the rabble-sleeve is thesame in all respects as the corresponding sleeve of the roastingchambercarriage, .and therefore need not be shown or described in detail. Thecoolinghearth is provided with longitudinal side bars 83 to keep the orein place thereon during the manipulation necessary to the coolingoperation.

. Motion is transmitted from one of the shafts 32 to one of the shaftsby a chain 84, engaging sprocket-wheels 85 and 86, fast on therespective shafts. The two shafts 70 are connected by a transverse shaft87, the shafts 70 having beveled gears 88, engaging gears 89, fast onthe extremities of the transverse shafts.

The manner of carrying or elevating the ore from the discharge extremityof the roastingchamber to the receiving extremity of the cooling-hearthabove, as well as the construction whereby this function isaccomplished, will now be described.

At the extremity of the roasting-chamber the hearth is provided with anopening communicating with an opening in the end wall of the chamber, inwhich is located a chute 90, provided with anormally closed hingedcutoff blade 9l,located near its discharge extremity, which protrudesthrough the opening in the wall of the chamber. -The chute has a widthequal to the entire width of the roasting-chamber, in the rear of whichis located a sprocket-wheel 92, which is engaged by an endless chain 93,which also engages sprocketwheels 94:, 95, and 96, suitably mountedabove the roof of theroasting-chamber. There are two chains and two setsof these sprocketwheels,one chain and one set of wheels beingon eachside of the machine. Each chain 93is operated from a shaft 70 throughthe medium of chain 97, engaging sprocket-wheels 98 and 99, fast onshafts 100 and 101, respectively. Motion is communicated to the shaft100 from the shaft70 through the medium of gears 102 and 103. A smallergear lO l on the shaft 101 meshes with a similar gear 105, which in turndiate gear 105 is employed to cause the chain 93 to travel in thedirection indicated by the arrows in Fig. 3 when the shafts70 areturning in a direction to cause the forward movement of therabble-carriage. To the two chains 93 is attached a bucket 108, having alength equal to the width of the dischargechute 90. ,A quantity of oreis discharged through this chute every-time the rabble-carriage reachesits limit of rearward movement. The movement of the bucket and itscarryingchains is so timed that the bucket is inposition to receive eachore discharge from the chute, this position being best shown in Figs. 3and 1].. As soon as the ore is discharged the rabble-carriages of boththe roasting and cooling hearth start forwardly, and the chains 93travel in the directions indicated by the arrowin Fig. 3, whereby thebucket 108 iselevated. This bucket maintains its upright position untilit reaches the dotted-line position A farthest to the right in Fig. 11.Its front side, which is vertical, then engages an offset 109, formed ina bar 110, mounted on the rear extremity of the cooling-hearth,wherebythe bucket is tipped onto its front side or to the positionB inFig. 11,after which the top of the bucket as the latter is drawn forwardlyengages an offset 112,which tips the bucket to the inverted positionO,whereby theoreis du mped on the rear extremity of the cooling-hearth63. By the time this has occurred the rabble-carriages have reached theforward exin the direction opposite that indicated by the arrows in Fig.3, and the travel of the bucket and its carrying-chains is so regulatedwith reference to the travel of the rabble-carriages that the bucketjust reaches its position immediately below the discharge-month of thechute in time to receive the ore discharged from the chutesimultaneously with the arrival of the rabble-carriage at its rearwardlimit of movement in the roasting-chamber, after which therabble-carriages begin their forward movement and the operation of ele-'vating and dumping the bucket is repeated.

The cut-off 91 in the discharge-chute opens in response to the downwardpressure of the ore-charge, but closes by gravity as soon as the oreleaves the chute, thus cutting off the entrance of air to theroasting-chamber.

Attention is called to the fact that the rabble plows or blades of thecooling-hearth are arranged to carry the ore forwardly on said hearth,while the rabbles of the roastingheart-h are arranged to cause the oreto travel rearwardly thereon, as heretofore explained. In other respectsthe operation of the rabbles on the two hearths is precisely the same.

Having described the mechanism of my improved roasting and coolingapparatus in detail, I will proceed to describe connectedly, butbriefly, the various steps in the operation of the same.

The heat from the fire box or boxes 7 enters the roasting-chamber andtravels forwardly therein, the smoke and products of combustion escapingthrough openings E in the forward extremity of the hearth into the flueH below, whichleadstothestack. (N0tshown.) The ore to be treated isdischarged into the hopper 13 and passes thence through theinstrumentality of the feed-screw 14c to the forward extremity of theroasting-hearth 12, where it is acted on by the rabble-plows and causedto travel gradually toward the rear extremity of the roasting-chamber, aquantity being finally discharged at predetermined intervals through thechute 90 into the bucket 108, in which it is elevated and dumped uponthe cooling-hearth, as heretofore described. As soon as therabble-carriage reaches the rear extremity of the roasting-chamber oneof the side bars 16 of the carriage engages the crank-arm 51 andoperates the belt-shift ing mechanism by virtue of the connectiondescribed, whereby the motion of the shafts 32 is reversed, causing therabble-carriage to begin its forward movement. Simultaneously with thereversing of the movement of the shafts 32 the rabble-sleeve 18 isturned one-fourth of a revolution through the action of a trip 24 tothrow the rabble-plows to the horizontal or inoperative position, asshown in Fig. 14, whereby the plows in the roasting chamber are idleduring the forward movement of the rabble-carriage, while therabbleplows of the cooling-hearth carriage are adjusted to occupy thevertical or operative position, whereby the ore is caused to travelforwardly on the cooling-hearth and finally discharged at its forwardextremity. During the forward movement of the rabble-carriages thebucket 108 is elevated and dumped. As soon as the roasting-hearthcarriage reaches its forward limit of movement one of its side bars 16acts on the crank-arm 49 and operates the belt-shifting mechanism toreverse the movement of the shafts 32 and 70, whereby the carriagesbegin their rearward movement, and during this rearward movement theorebucket 108 is returned to its position at the discharge extremity ofthe chute 90 ready to receive the charge of roasted ore therefrom.Simultaneously with the operation of the beltshifting devices when thecarriage of the roastingchamber has reached its forward limit ofmovement the valves 58 of the waterpipe branches 57 are opened throughthe' medium of the levers 61, which are acted on by the bars 16 of therabble-carriage, whereby the latter is supplied with the necesssarywater forcooling the carriage mechanism during a complete trip or arearward and forward movement in the roasting-chamber. same time therabble-sleeves of the two rabble-carriages are actuated,the one in theroastin g-chamber to throw the plows to the vertical or operativeposition and the one above the cooling-hearth to the horizontal orinoperative position, it being'understood that the ore is made to travelin opposite directions on the two hearths.

\Vhile the mechanism for supplying water to the rabble-carriage is shownin the drawings at one extremity only of the roastingchamber, it isevident that a similar set of mechanism may be employed at the oppositeextremity of the said chamber, so that the carriage may receive a freshsupply of water at each extremity of the chamber. This is clearly withinthe scope of the invention and is simple duplication.

Having thus described my invention, what I claim is 1. In aroastingapparatus, the combination with a roasting chamber and hearth, of arabble-carriage located in the roasting-chamber and comprising hollowside bars forming water-receptacles, open to permit evaporation in theroasting-chamber, a transverse bar provided with rabble plows orblades,the side bars occupying positions on opposite sides of thehearth, and means for propelling the rabblecarriage.

2. In an apparatus of the class described, the combination with aroasting chamber and hearth, of hollow side bars formingwater-receptacles located on opposite sides of the hearth, a transversebar connecting the side bars, and a sleeve movably mounted on thetransverse bar, and provided with rabble plows or blades, and means forpropelling the rabble-carriage.

3. The combination with a combustion chamber and hearth, of hollow sidebars forming water receptacles located on opposite At the sides of thehearth, a hollow transverse. bar connecting the side bars, and havingopen v ends to allow the water to enter from the side I cated in thesaid chamber and composed of hollow side bars forming water-receptacles,hollow transverse bars connecting the side bars and open to allow thewater to enter from the side bars, and rabble plows or blades mounted onone of the transverse bars, the side bars being located on oppositesides of the hearth, and suitable means for propelling therabble-carriage.

r 5. The combination with a chamber and hearth, and asource of heatconnected with the chamber, ofv a rabble-carriage composed of hollowsidebars forming water-receptacles openat the top to permit freeevaporation, a hollow transverse barconnecting the side bars and open toallow the water to enter from the side bars, rabble plows or bladesmounted on the transverse bar, and suitable means for propelling therabble-carriage.

(5. The combination with a chamber, a hearth, and a source of heat, of arabble-carriage located in the chamber and composed of hollowside barsforming water-receptacles located on opposite sides of the hearth, andopen at the top, the lower edges of the bars being provided with coggedracks, transverse bars connecting the side bars and open to allow thewater to enter from the side bars, rabble plows or blades mounted on oneof the transverse bars, and propelling-wheels suitably journaled alongthe sides of the hearth and provided with cogs engaging the racks of theside bars for actuating the rabble-carriage.

7. The combination with a hearth, of side bars located on opposite sidesof the hearth,

'theirlower edges being partly cogged and partly plain, transverse barsconnecting the side bars, rabble plows or blades mounted on one of thetransverse bars, and wheels located along the sides of the hearth forsupporting and propelling the rabble-carriage, the said wheels having acogged .zone to engage the cogs of the side-bar racks, and a plain zoneto engage the plain portion of the rack-bars, forming the support forthe carriage, .whereby the cogged portions of the wheels are relieved ofthe weight and only required to perform the propelling function,substantially as described.

8. In an apparatus of the class described, thecombination with a hearthupon which ore may be spread for. roasting or cooling purposes, of sidebars arranged to travel on opposite sides of the hearth, transverse barsconnecting the side bars, wheelslocated along the hearth sides andengaging the side bars in operative relation for propelling purposes, arabble-sleeve movably mounted on one of the transverse bars, said sleevebeing provided with plows or blades, a toothed wheel fast on therabble-sleeve, a pawl or dog pivotally mounted. on one of the side barsand engaging the toothed wheel to prevent rotationin one direction, anda trip located at: each extremity of the hearth for 'engagingthe toothedwheel of the rabble-sleeve and imparting a partial rotation thereto,substantially as described. and for the purpose set forth.

9..The combination with a hearth, of side bars arranged to travel alongthe hearth on opposite sides, connecting-bars extending transverselyacross the hearth, a sleeve movably mounted on one of the transversebars, a toothed wheel fast on each extremity of the sleeve, a dog orpawl pivoted on each side bar and engaging the adjacent toothedwheel toprevent, the rotation of the latter in one. direction, and atrippingdevice suitably located to engage and actuate the, toothedwheel, whereby a partial rotation is imparted tothe. rabble-sleeve atpredetermined intervals,sub-

stantially as described and for the purpose.

set forth. p

10. The combination with a hearth, of carriage side bars located andarranged to travel.

on opposite sides of the hearth, bars extending transversely across theheart-hand con-. meeting the side bars,- a sleeve movably mounted on oneof the transversebars and composed of interlocking sections, rabbleplowsor blades mounted on the sleeves, and means for imparting a partialrotation to the sleeve at predetermined intervals, substantially asdescribed. 11. The combinationwith a hearth, of car'- riage side barsarranged to move on opposite. sides of the hearth, a transverse barconnect ing said side bars, a sectional sleeve mounted to rotate on saidbar, each sleeve-section being provided with two rabble blades or plowsdiametrically located, means for lockingthe sleeve against movement inone direction, and means for impartinga partial rotation to therabble-sleeve in the opposite direction at predetermined intervals,substantially as described.

- 12. The combination with a hearth, of side bars located and adapted totravel on opposite sides of the hearth, a bar extending transverselyacross the hearth and connecting the side bars, a sleeve mounted torotate onsaid bar, rabble plows or blades diametricallylocated onopposite sides of the sleeve, the oppositely-located blades beingparallel and adjustably connected with the sleeve, substantially asdescribed.

13. The combination with a hearth, of carriage side bars arranged andadapted to travel on opposite sides of the hearth, a transverse barconnecting the side bars, a sleeve mounted to rotate on said bar,rabbleplows or blades diametrically located on opposite sides to preventthe movement of the sleeve in one direction, and a depending trippingdevice arranged to engage each toothed wheel and impart a partialrotation to the rabble-sleeve in the opposite direction, the trippingdevice being pivoted to swing freely from the vertical position in onedirection, but locked against movement in the opposite direction,substantially as shown and described.

14. The combination with a hearth, of side bars located and arranged totravel on opposite sides of the hearth, transverse bars connecting theside bars, rabbles mounted on one of the transverse bars, the side barshaving cogged racks on their lower edges, cogged propelling-wheelslocated along the sides of the hearth at suitable intervals, andengaging the side-bar racks, shafts extending longitudinally along thesides of the hearth and geared to the carriage propelling wheels, meansfor operating the shafts and means connected with the operatingmechanism and acted on by the rabble-carriage at each end of the hearth,for automatically reversing the movement of the longitudinal shafts andcarriage-propelling wheels, whereby the carriage is made to move backand forth over the hearth, substantially as shown and described.

15. In an apparatus of the class described, the combination ofaeombustion-chamberand a hearth, with a rabble-carriage provided withside bars arranged to travel on opposite sides of the hearth, transversebars connecting the side bars, rabbles mounted on one of the transversebars, propelling-wheels located at suitable intervals along the hearthsides and engaging the carriage side bars in operative relation, shaftslocated outside of the chamber and geared to the propelling-wheels foroperating the carriage, means for operating the shafts and meansconnected with the shaft-operating mechanism, located at each end andoutside of the chamber, for reversing the movement of theoperating-shafts, said means being actuated by a carriage side bar, theend walls of the chamber being open to allow the said bar to protrudefor the purpose set forth.

16. The combination with a chamber and a hearth, of side bars locatedand arranged to travel on opposite sides of the hearth, a transverse barconnecting the side bars and provided with rabble blades or plows, meanslocated outside of the chamber for operating the carriage and causing itto move longitudinally over the hearth, and means exteriorly located ateach extremity of the chamberfor reversing the movement of thecarriage-operating mechanism, the said reversing means being actuated bythe rabble-carriage, the end walls of the chamber being provided withopenings to allow the carriage side bars to protrude for the purpose setforth.

17. .In an apparatus of the class described, the combination with acombustion-chamber and a hearth, of a rabble-carrier located in saidchamber and having a part arranged to protrude at each end of thechamber whose end walls are provided with openings for the purpose,means for causing the carriage to travel longitudinally, and meanslocated at each end of the chamber and acted on by the protruding partof the rabble-carriage, whereby the carriage-operating mechanism isantomatically reversed, and the carriage made to travel back and forthin the chamber, substantially as described.

18. In an apparatus of the class described, the combination with aroasting chamber and hearth, of a rabble-carriage provided with sidebars located and arranged to travel on opposite sides of thehearth,propelling-wheels engaged by the carriage side bars in operativerelation, two longitudinal shafts located outside lhe chamber andconnected to operate the rabblecarriage-propelling whee1s,the twolongitudinal shafts being connected to operate in unison, fast and loosepulleys connected with one of the longitudinal shafts, belts for thepulleys, belt-shifting devices for reversing the rotation of the shaft,the rabbleearriage being provided with a part protruding throughopenings formed in the end walls of the chamber, and means located ateach end of the chamber and connected with the belt-shifting devices,for operating the latter, the said means being automatically actuated bythe carriage-protruding part, substantially as described.

1!). In an apparatus of the class described, the combination with achamber and hearth, of a rabble-carriage located in said chamber whichis provided with openings in its end walls, the carriage being providedwith parts adapted to protrude through said openings, a shaft locatedoutside the chamber and connected to cause the rabble-carriage to movelongitudinally therein, means for operating said shaft, and meanslocated exteriorly at each end of the chamber and arranged to beactuated by the carriage-protruding parts, for reversing theshaft-operating mechanism, substantially as described.

20. In an apparatus of the class described, the combination with achamber and hearth, of a rabble-carriage arranged to move longitudinallyin said chamber which is provided with openings in its end walls, thecarriage being provided with parts adapted to protrude through saidopenings, a shaft located outside the chamber, means connected with andoperated by said shaft for actuating the carriage in the chamber, fastand loose pulleys mounted on said shaft, belts connected with saidpulleys, belt-shifting devices, and means located at each end of thechamber and connected with said devices for shifting the belts andreversing the rotation of the shaft, said means being actuated by theprotruding parts of the carriage, whereby the latter is caused to travelback and forth in said chamber, substantially as described.

21. In an apparatus of the class described, the combination with achamber and hearth,

,of a-rabble-carriage arranged to move longioutside of the chamber,means connected with and operated by said shaft for actuating thecarriage in the chamber, fast and loose pulleys mounted on said shaft,belts connected with said pulleys, belt-shifting devices, a,

- rock-shaft on which said devices are mounted, an arm also fast on therock-shaft, another rock-shaft provided with a'crank-arm, a linkconnecting the two arms, a third arm mounted on one of the rock-shafts,and lyingin the path of the carriage-protruding part at the end of thechamber, whereby the belt-shifting devices are'actuated and the movementof the carriage-operating shaft reversed, substantially as described.

22. In an apparatus of the class described, the combination with achamber and hearth, of a rabble-carriage located and arranged to movelongitudinally in said chamber which is provided with openings in itsend Walls, the carriage having part-s adapted to protrude through saidopenings, a shaft located outside of the chamber, means connected withand operated by said shaft for actuating the carriage in the chamber,pulleys mounted on said shaft, belts connected with said pulleys,belt-shifting devices, a rock-shaft on which said devices are mountedand made fast, an

arm also fast on the rock-shaft, another rock-.

shaft provided with a crank-arm, a link connecting the two arms, a thirdarm mounted on one of the rock-shafts and lyin gin the path of thecarriage-protruding part at one end of the chamber, a rock-shaft locatedat the opposite end of the chamber, a crank-arm fast on the last-namedrock-shaft, and located in the path of the carriage-protruding parts, arocking bar fast on the rock-shaft at each extremity of the chamber,each bar projecting an equal distance from the rock-shaft in oppositedirections, and rods or cables connecting the corresponding extremitiesof the two rocking bars, whereby as soon as the rabblecarrier reachesits limit of movementin either direction,its operating mechanism isreversed and it is caused to travel in the opposite direction.

23. The combination with a roasting or dryingv chamber, and a suitablehearth, of arabble-carriage movable longitudinally in the chamber andprovided with hollow side bars forming water-receptacles, a hollowtransverse rabble-bar connecting the side bars and open to allow thewater from the side bars to enter, and a valve-controlled water-supplyconduit located exteriorly at one end of the roasting-chamber, forsupplying the carriage withwater, thevalve of the conduit beingautomatically opened by the movement of the carriage.

24. The combination with a roastin g or drying-chamber and a hearth, ofa rabble-carriage located in said chamber and adapted to hold water,means for operating the carriage, whereby it is made to travel back andforth in said chamber which is provided with openings in its end walls,the carriage having a part adapted to protrude through said openin gs, avalve-controlled water-conduit located outside the chamber, and meansfor opening the valve, said means being actuated by the protruding partof the carriage, which protrudin g part is connected to receive thewater and conduct it to the other carriage parts.

. 25. The combination with a roasting chamber and hearth, of arabble-carriage adapted .to move back and forth in said chamber andprovided with hollow side bars forming waterrecep'tacles, the end wallof the chamber being open to allow the said bars to protrude, a hollowrabble-bar connecting the side bars and open to allow the water from theside bars to enter, a water-supply conduit exteriorly located at one endof the chamber, a valve for controlling the discharge of water from saidconduit, operating means connected with the valve, said means beingactuated by aprotruding side bar of the carriage, whereby the Valve isautomatically opened and closed at predetermined intervals, the said barbein g in position to receive the-necessary water for supplying thecarriage.

26. In an apparatus of the class described, the combination with aroasting chamber and hearth, of a' rabble-carriage located therein andadapted to move back and forth, said carriage having side bars formingWater-receptacles open at the top, and a hollow transverse barconnecting the side bars andcommunicatingtherewith to permitcirculationof water, rabble blades or plows mounted on the transversebar, one end wall of the roasting-chamber having openings to allow thehollow side bars to protrude, a water-supply conduit exteriorly located,a valve for controlling the discharge from said conduit, and meansconnected with the valve and lying in the path of the free extremitiesof the side bars, whereby the said valve is operated, substantially asdescribed. 7

27. In anapparatus of the class described, the combination with aroasting chamber and hearth, of a rabble-carriage constructed to holdwater and provided with a part adapted to protrude from the end of thechamber the latter being provided with an opening for the purpose, aneXteriorly-located water-supply device, a valve connected with saiddevice and arranged to be opened by the protruding part of therabble-carriage when travelingin one direction, and closed by said partwhen traveling in the opposite direction, substantially as described.

28. The combination with a chamber and hearth, of a rabble-carriageadapted to hold water and being arranged to protrude from the end of thechamber whose wall is provided with an opening for the purpose, awater-supply conduit exteriorlylocated and pro IIO vided with a valve, alever connected with the valve and lying in the path of the protrudingpart of the carriage, whereby the lever is actuated to open the valvewhen the carriage is moving in one direction, and to close the valvewhen the carriage is moving in the opposite direction, substantially asdescribed and shown.

29. The combination with a roasting chamber and hearth,of arabble-carriage constructed to hold water and provided with a partadapted to protrude from the roasting-chamber and conduct water to theportion of the carriage within the chamber, the latter having an openingin its end wall to allow the said parts to protrude, water-supply meansprovided with a valve controlling the discharge-opening, a leverconnected with said valve and provided with two arms, one of which liesin the path of the carriage-protruding part when it is moving in onedirection, whereby the lever is actuated to open the valve and allow thewater to flow therefrom into the protruding part of the carriage, theother lever-arm being thrown to a position to be engaged by the carriageduring its movement in the opposite direction, whereby the valve isclosed.

30. The combination with a roasting chamber and hearth, of arabble-carriage located therein and adapted to move back and forth asdescribed, the said carriage having a protruding part adapted to receiveand conduct water to the other parts of the carriage, the said partbeing open to permit the escape of water by evaporation in theroasting-chamber, the end wall of the chamber having an opening to allowthe said part of the carriage to pass through, substantially asdescribed.

31. The combination with a chamber and hearth, of a rabble-carriageadapted to hold and retain water and .permitting escape only byevaporation, said carriage having a protruding part adapted to receiveand conduct water to the parts of the carriage Within the chamber, and awater-supply source provided with avalve arranged to be opened andclosed by the protruding part of the carriage as it moves in oppositedirections, substantially as described.

32. The combination with a chamber and hearth, of a carriage arranged tomove back and forth in said chamber and provided with a protruding partadapted to receive water and conduct it to the other parts of thecarriage which is constructed to contain water, permitting escape onlyby evaporation, a water-supply source located outside the chamber, avalve controlling the discharge from said source, a triple-armed lever,one arm of which is connected with the valve, another arm lying in thepath of the carriage-protruding partas it moves forwardly or out of thechamber, whereby the lever is actuated to open the valve, the thirdlever-arm being thrown by said action into the path of the protrudingpart as it moves in the opposite direction,whereby the lever is actuatedto close the valve.

33. The combination with a roasting chamber and hearth, of arabble-carriage located in the chamber and constructed to hold water andpermit escape by evaporation, said carriage having a protruding partadapted to receive water from a source outside of the chamber, andconduct it to the portion of the carriage within the chamber, and meanslocated outside the chamber and automatically controlled by thecarriage-protruding part, whereby the carriage -is supplied with waterwhile the said carriage part is outside of the chamber, the waterdischarge being cut oit when the said part moves into the chamber.

34. The combination with a roasting chamber and hearth, ot' arabble-carriage arranged to move back and forth within the chamber, thesaid carriage being constructed to hold water and permit escape byevaporation, the said carriage having a protruding part adapted toreceive and conduct water from a point outside the chamber to theportion of the carriage within the chamber, the wall of the chamberhaving an opening through which the said carriage part passes, awater-supply source located outside the chamber and provided with avalve, a crank-arm attached to the valve-stem, a triple-armed lever, onearm of which is connected with the valve-crank, another arm located inthe path of the protruding part as it moves out of the chamber, wherebythe lever is actuated to open the valve and allow the water to pass intothe protruding part of the carriage, the third arm of the lever beingthrown into the path of the carriage protruding part as it moves in theopposite direction orinto the chamber,whereby the lever is actuated toclose the valve.

35. The combination with a chamber and hearth, of a rabble-carriagearranged to move back and forth within the chamber and over the hearth,the said carriage being adapted to hold water and permit its escape byevaporation, the carriage being also provided with a protruding partadapted to receive water and conduct it to the part of the carriagewithin the chamber, the wall of the chamber having an opening to allowthe carriage protruding part to pass outside the chamber, a watersupplysource located outside the chamber, a valve controlling the escape ofwater from said source, a crank connected with the valve, a lever, alink connecting the said crank with one arm of the lever which isprovided with another arm lying in the path of the protruding part as itmoves out of the chamber, whereby the valve is opened, the lever havinga third arm which is engaged by the carriage protruding part as it movesin the opposite direction, whereby the valve is closed.

36. The combination with a roasting chamber and hearth, and acooling-hearth located above the roasting-chamber, of a discharge-

